522 PROCEEDINGS OF THE ACADEMY OF [August, 



Clausilium (PI. XXVII, figs. 19, 20) with the apex strongly 

 projecting, finger-like, the palatal margin near it being strongly 

 excised and concave ; and it is deeply excised on the palatal side of 

 the filament. 



This form approaches var. goniopoma, but differs in the fine stri- 

 ation, "and somewhat in the shape of the clausilium. 



Clausilia oostoma var. goniopoma n. sp. PL XXVII, figs. 11, 12, 13, 14. 



Shell somewhat fusiform, the upper half tapering, attenuated, 

 lower half somewhat swollen ; dull light-yellow. Sculpture of rather 

 strong and separated folds or ribs, the upper whorls smoother, worn. 

 Apex small. Whorls 11 to 114, moderately convex, latter half of 

 the last conspicuously compressed. Aperture subvertical, piriform, 

 the peristome white, continuous and somewhat thickened. Superior 

 lamella marginal, oblique, continuous with the spiral lamella, which 

 penetrates to a point above the superior lamella. Inferior lamella 

 forming a strong, subhorizontal fold, approaching the superior 

 lamella ; inside it ascends in a broad spiral, and penetrates deeper 

 than the spiral lamella. The subcolumellar lamella emerges. The 

 principal plica is short, rather weak and lateral. Palatal plicse two, 

 the upper of moderate size or small, the lower larger. 



Length 21, diam. nearly 5 mm. 



Length 19.8, diam. 4.5 mm. 



Clausilium (PI. XXVII, figs. 11, 12) very broad below, the 

 apical end bent at a right angle to the rest of the plate, thickened, 

 narrow and mucronate, excised and thin on the palatal side; above 

 it is a little excised on the columellar side of the filament. 



Wakayama, Kii. Types No. 83,286, A. N. S. P., from No. 

 926 of Mr. Hirase's collection. 



In general external shape, as well as in the lamellae, this form 

 resembles C. oostoma Mlldff . (surugce Pils. ), but it differs in the 

 far coarser sculpture and in the peculiarly bent and attenuated 

 distal end of the clausilium. 



Whether the forms oostoma, dactylopoma and goniopoma are to be 

 regarded as distinct species or as subspecies remains a subject for 

 further investigation, as each is yet known from a single locality, 

 and is constant in its characters, so far as may be judged by the 

 material before me. The salient characteristics of the three forms 

 may be succinctly tabulated thus : 



